ESTRO 2024 - Abstract Book

S621

Clinical - Breast

ESTRO 2024

Results:

In the Alliance A011202 trial, the 7-year DFS was 80.1% in both arms. However, clinical lymphedema and the ODB were greater in patients who underwent axillary lymph node dissection than in those who underwent sentinel lymph node biopsy followed by full regional nodal irradiation (RNI). In the PORT-N1 trial, the control arm (post mastectomy radiotherapy [PMRT] or whole-breast irradiation [WBI] with RNI) had an ODB of 0.254, while the experimental arm (no PMRT or WBI alone) had a comparable ODB of 0.255. In the RAPCHEM trial, the radiotherapy field did not impact the 7-year DFS in intermediate or high-risk patients. However, there was a mild increase in ODB with a larger irradiation field. In the RT-CHARM trial, we identified factors associated with the major complication rate, which ranged from 18.3% to 22.1%.

Conclusion:

Our BN model was able to predict the outcomes of ongoing prospective trials, supporting the reported outcomes and assumptions of these trials. In addition, the model demonstrated the ODB in different arms, with an emphasis on quality of life.

Keywords: In silico, Bayesian, (y)pN1

2202

Proffered Paper

Validating the ESTRO target consensus: pattern of breast cancer failures in the DBCG Skagen trial 1

Kristine Wiborg Høgsbjerg 1,2 , Mette Skovhus Thomsen 3 , Else Maae 4 , Martin Berg 5 , Mette Holck Nielsen 6 , Ebbe Laugaard Lorenzen 7 , Maja Vestmø Maraldo 8 , Kristian Boye 8 , Lars Stenbygaard 9 , Ingelise Jensen 10 , Sami Aziz-Jowad Al Rawi 11 , Kirsten Legaard Jacobsen 11 , Louise Wichmann Matthiessen 12 , Karen Andersen 12 , Birgitte Vrou Offersen 1,2,13 1 Aarhus University Hospital, Department of Experimental Clinical Oncology, Aarhus, Denmark. 2 Aarhus University Hospital, Department of Oncology, Aarhus, Denmark. 3 Aarhus University Hospital, Department of Medical Physics, Aarhus, Denmark. 4 Vejle Hospital, University of Southern Denmark, Department of Oncology, Vejle, Denmark. 5 Vejle Hospital, University of Southern Denmark, Department of Medical Physics, Vejle, Denmark. 6 Odense University Hospital, Department of Oncology, Odense, Denmark. 7 Odense University Hospital, Laboratory of Radiation Physics of Oncology, Odense, Denmark. 8 Copenhagen University Hospital - Rigshospitalet, Department of Clinical Oncology, Center for Cancer and Organ Diseases, Copenhagen, Denmark. 9 Aalborg University Hospital, Department of Oncology, Aalborg, Denmark. 10 Aalborg University Hospital, Department of Medical Physicsment of Oncology, Aalborg, Denmark. 11 Zealand University Hospital, Department of Oncology, Næstved, Denmark. 12 Copenhagen University Hospital – Herlev and Gentofte, Department of Oncology, Copenhagen, Denmark. 13 Aarhus University Hospital, Danish Centre for Particle Therapy, Aarhus, Denmark